Abstract: Objective: To study the antitumor effects of extracellular polysaccharides from Morchella esculenta (EPM) and the immunological function on S180 tumor-bearing mice. Method: EPM was intragastrically given to S180-bearing mice at the dose of 200 mg/kg and 400 mg/kg. Normal sodium and cyclophosphamide were taken as blank control and positive control respectively. The tumor weight, immunologic organ weights and life span of S180-bearing mice were measured. S180 tumor cells were incubated with various concentrations of EPM for 24 h, and antiproliferative activities against tumor cells were determined by MTT assay. Result: EPM significantly increases the spleen index, percent of T-lymphocyte, macrophage phagocytic index and prolongs survival time of S180-bearing mice.The inhibiting tumor rates at the low and high does are 49.04% and 64.42% respectively. EPM can kill S180 tumor cells directly in vitro, with the highest inhibiting rate 46.3% at the dose of 50μg/well.Conclusion: EPM has significant antitumor effects and improves immunological function.

Key words: Morchella esculenta, extracellular polysaccharide, antitumor, immunological function